Rubber Hose Vetus tube stack

[txg]

Our boat has a Vetus M4.35 (base Mitsubishi S4L) with about 1000 hours, installed in 2015.



For some time now, the engine smokes white with a light tint of grey when run above 2000rpm. It only smokes under load and only when it is warmed up. It never sounds the high temperature alarm.



So far, i changed the coolant, flushed the heat exchanger with vinegar and measured raw water flow which is a little bit on the low side.


Before deciding if i should do a rebuild or order a new water pump">raw water pump i decided to take the tube stack out of the heat exchanger to make sure this wasn't the cause of the problem. Normally, this heat exchanger should look like this:


http://i64.tinypic.com/34remh0.jpg


As far as i understand, this cover is made to help the coolant run through in between the tubes.


See attached picture what ours is looking like, the rubber cover has widened. I don't know if this is because of a wrong coolant or if maybe salt water has entered the coolant loop.



Now my questions are:


-Do you think this could be a reason for the engine smoking? As the tubes itself were mostly clean on the raw water side, i'm still thinking this smoking problem is caused by low water flow due to a worn-out pump.


-What would you do about the rubber cover? Is this a common design? Haven't seen this on other engines but my experience is limited.



-Is there a place in Miami where i could get such a rubber cover? Or should i simply leave it off? Our engine is a 33hp and the same construction is used on the 42hp model.

[Sailmonkey]

Are you seeing smoke or steam?

The engine is not overheating? What makes you think you have a cooling problem at all?

Vinegar isn’t really going to clean the tubes, you need something a little more aggressive like CLR.


White smoke, if not steam, usually indicates an injector that’s not atomizing correctly. The white is diesel fuel vapor.

I would contact Cetus about the sleeve, looks like something simple like maybe a heat shrink tube.

[txg]

It could be steam as well, hard to tell.



I have no temperature gauge, so i don't know if the engine is running hotter than it used to. But it didn't smoke when it was newer, so something changed. The injector problem could be possible as well.



I just contacted Vetus, in the past they have not been of much help but maybe it will work better this time.



According to Vetus the engine should pump 50L/min at full speed of 3000rpm. I assumed that pump capacity is roughly linear to rpm, so at idle of 800rpm it should be about 13L/min. What i measured was more like 7-8L/min.

[txg]

A while ago i did a short Video. This is our engine in our Dufour 35 with a 15x11 Flexofold 3-Blade at full throttle, doing about 7 knots at 2800 rpm.



Video Link:

https://youtu.be/GxBi1TRbkuY


Does this look like smoke or steam?


Is it common for injector problems to happen only on high rpm (for us, the smoking starts at about 2000rpm) and with the engine under load and warmed up?

[Sailmonkey]

Originally Posted by txg

A while ago i did a short Video. This is our engine in our Dufour 35 with a 15x11 Flexofold 3-Blade at full throttle, doing about 7 knots at 2800 rpm.



Video Link:

https://youtu.be/GxBi1TRbkuY


Does this look like smoke or steam?


Is it common for injector problems to happen only on high rpm (for us, the smoking starts at about 2000rpm) and with the engine under load and warmed up?

That's a pretty awful video, but it looks like steam, and you have no shortage of water.

[txg]

Originally Posted by Sailmonkey

That's a pretty awful video, but it looks like steam, and you have no shortage of water.

I agree to the awfulness


How can there be steam now if there is no shortage of water and there has been no steam earlier? Water temperatures haven't changed.



Any other idea about the rubber cover? A boat technician friend told me to just leave it out and currently i tend to try that out. He says he has not seen such a construction before.

[jmschmidt]

Sailmonkey most likely has your problem figured out. Doubtful if you have a cooling problem. I've never heard of a cooling problem putting out smoke, at least not until the engine catches fire.

White or slightly blueish smoke on warm up is usually injectors. Stick your bare hand in the exhaust smoke on warm up. If it feels slightly oily this is most likely unburn fuel from one of more bad injectors. I just had my four rebuilt for $272.25. They are simple to remove and replace.

I have the same 33 Mitsubishi/Vetus (older model) with the same heat exchanger core but that black thing looks totally weird. My engine has the core inside the combination exhaust manifold/hear exchanger. About 10 years ago I had to replace this unit and the replacement was exactly like the old one except in cast aluminum rather than iron.

The HE core (at least in my engine) is simple to remove and rod out by carefully using a wooden dowel slightly smaller the tubes in the core. I stress carefully and slowly. No caustic chemicals needed, just a little soap for lubrication, and water. Mine has O-rings at either end. Replacements can be purchased at any good hardware store.

[The Way]

Originally Posted by jmschmidt

Sailmonkey most likely has your problem figured out. Doubtful if you have a cooling problem. I've never heard of a cooling problem putting out smoke, at least not until the engine catches fire.

White or slightly blueish smoke on warm up is usually injectors. Stick your bare hand in the exhaust smoke on warm up. If it feels slightly oily this is most likely unburn fuel from one of more bad injectors. I just had my four rebuilt for $272.25. They are simple to remove and replace.

I have the same 33 Mitsubishi/Vetus (older model) with the same heat exchanger core but that black thing looks totally weird. My engine has the core inside the combination exhaust manifold/hear exchanger. About 10 years ago I had to replace this unit and the replacement was exactly like the old one except in cast aluminum rather than iron.

The HE core (at least in my engine) is simple to remove and rod out by carefully using a wooden dowel slightly smaller the tubes in the core. I stress carefully and slowly. No caustic chemicals needed, just a little soap for lubrication, and water. Mine has O-rings at either end. Replacements can be purchased at any good hardware store.

For what it's worth, Beta recommends soaking the tube-stack in white vinegar overnight during its annual cleaning.

Fair winds,
Jack

[s/v Jedi]

If you have access to the product (US I guess) then I recommend BarnacleBuster because it's concentration is known to be just right, i.e. not as weak as vinegar and not so strong to eat up your metals.

But in the picture the heat exchanger looks clean. Look inside the channels if they all look to be open/clean as well and if so don't even bother cleaning it.

[rbk]

x2 for the injectors, before sending them all away, pull and check the spray pattern, look for one that is erratic or just dribbling. Did you change your oil recently? Maybe the wrong grade? Too much? Also could be your air intake, clogged filters can cause white /grey smoke as well. If none of those check out, check all your fuel line connections then pull your valve cover and check for a stuck valve, and proper head bolt torque. Check in order below:
-Cold starting temps
-Air filter
-Oil level and grade
-Injectors
-Stuck valve
-Injection pump
-Head gasket failure
-Ring failure
If you get to pulling the head stop and reassess

[NCboatrx]

I believe that the rubber cover is a necessary part. There is probably a divider in the manifold and all the coolant is guided around the raw water tubes and through the rubber tube to get the right amount of heat transfer. I have never seen a piece of rubber tubing used like this as other manufacturers use brass or cupro nickel or aluminum. If I am correct, then leaving the rubber off may cause the engine to overheat if pushed hard.
In the photo of the new Vetus tube stack, the rubber tube appears to be a big piece of heat shrink.

[transmitterdan]

The “rubber” shrink tubing around the tube stack looks like it suffered a serious over temperature event. That may have destroyed the tubing’s “memory” and now it is not working to force water around the tubes. You can probably replace the tubing yourself if you can find it. I believe McMaster-Carr sell large diameter shrink tubing. You will need a couple big heat guns to shrink it. Don’t over shrink it as it can apply a lot of pressure to the tubes and even bend them.

[jimbunyard]

Slowed the video down, almost certainly steam. Try the bundle without the plastic tube, it can't hurt anything at this point. Depending on how the fresh water is routed, that loose shroud could be moving around and interfering with the flow, causing the engine to run hotter.

Of course that doesn't explain how the shroud got that way in the first place.

In my opinion a temperature gauge is a necessity.

[txg]

The engine never overheated, so that can't be the issue. If the measures i did till now (see below) will not help, i will get the injectors serviced, but that probably won't happen before our atlantic crossing.



Recent findings:


-Our water pump (the common jabsco 29460) stopped working completely when i did an impeller change. Interestingly, this was the case with two new impellers (one original vetus still in packaging), but it still kind of worked with the old wornout impeller. Anyways, i ordered a new one and put it in. The old pump hat 1000 hours on it and on these pumps there is no exchangeable cam. At about 300 bucks they are at least not as expensive as e.g. Yanmar pumps.



-I found out that the old O-rings on the heat exchanger were very brittle and there was maybe a leak between raw water side and coolant. The original Vetus O-Rings are FKM (same as Viton). I had a hard time finding these here and was wondering about why these are so brittle after just four years. After some research i found out FKM is NOT recommended for contact with coolant or hot water. Now i put in neoprene O-Rings which should be much better. I have no idea why Vetus did this.



-As always, Vetus itself was NO help at all. I sent them a proper description of my problem with the rubber hose on the tube stack with included pictures, and they did not get back to my questions at all, they simply sent me the part number of the whole tube stack. Their service is seriously horrible.



-I put the tube stack without the rubber hose back in. With the new raw water pump and the new O-rings everything ran fine today motoring backwards on the mooring for about 10mins. We will head out for a short sea trial tomorrow.

[s/v Jedi]

When my water pump stopped working and changing impellers got weird results, it turned out the problem was a restriction in the water flow through the exhaust injection elbow. I recommend you check it (do the bucket test, catch water from exhaust and calculate gallons/liters per minute

I verified by removing the water hose from the injection elbow and blow through the elbow (clogged).